In the related art, for example, a vehicle sunroof apparatus disclosed in JP 2000-108676A (Reference 1) is known (a so-called outer slide sunroof). In this apparatus, a link mechanism for supporting a movable panel includes a rear lift link which performs a swinging operation using a slide operation of a first shoe, a front lift link which performs a swinging operation using a slide operation of a second shoe, and a connecting rod which connects the rear lift link and the second shoe and causes the second shoe to perform the slide operation by the swinging operation of the rear lift link. Then, if the first shoe is caused to perform the slide operation, the rear lift link performs the swinging operation and lifts up a rear end of the movable panel. In a process thereof, the swinging operation of the rear lift link is transmitted to the second shoe via the connecting rod. The slide operation of the second shoe which is performed in response to the process causes' the front lift link to perform the swinging operation so as to lift up a front end of the movable panel. In the above-described manner, the movable panel performs a tilting-up operation.
Thereafter, the first shoe and the second shoe are slid. In this manner, the movable panel is slid outward while maintaining a tilting-up state, and an opening formed on a roof is brought into an opened state. In this case, an engagement structure set between the rear lift link and the first shoe is operated an as to cause the rear lift link to perform the swinging operation. Therefore, the setting of the engagement structure enables the movable panel to slowly perform the tilting-up operation.
Incidentally, in the vehicle sunroof apparatus disclosed in Reference 1, a movement amount (operation stroke) of the first shoe which is required from a fully closed state to a fully opened state represents a movement amount from the fully closed state via the tilting-up state to the fully opened state. Therefore, if the movement amount of the first shoe until the fully dosed state is shifted to the tilting-up state (hereinafter, referred to as a “tilting operation stroke”) increases, it is difficult to ensure the movement amount of the first shoe until the tilting-up state is shifted to the fully opened state, that is, an opening amount of the movable panel.
In contrast, the tilting operation stroke corresponds to a time interval in a high load state for making the movable panel ascend and descend. Accordingly, it is preferable to ensure that the tilting operation stroke have a longer period. If the tilting operation stroke decreases, a load per unit operation stroke increases. To that extent, increasing a size of an electrical driving source (motor or the like) for driving the first shoe becomes inevitable.
In a vehicle sunroof apparatus (outer slide sunroof) disclosed in Japanese Patent No. 4109583 (Reference 2), a configuration is proposed in which a guide rail protrudes forward so that the guide rail for sliding a shoe penetrates a front frame (housing). In this manner, for example, it is possible to increase the opening amount of the movable panel, or it is possible to enlarge a support span of the movable panel without impairing the opening amount of the movable panel.
However, an increase in the opening amount of the movable panel which is obtained by causing the guide rail to penetrate the front frame is less effective. Consequently, it is still difficult to ensure the opening amount.